For example, the automatic original document feeding device of the copying machine (a copier) generates various types of noises such as a driving sound of a motor for transporting an original document, a sound made when gears transmitting driving are meshed with each other, or a sound made when the original document rubs against or collides with a transporting guide.
In order to reduce such noise, a technique of eliminating sound having a specific frequency by using a Helmholtz resonator is known. However, due to sound deadening, when using the Helmholtz resonator, it makes the apparatus expensive, and a space for installing the Helmholtz resonator is also required.
In addition, in the related art, for noise countermeasures in the image forming apparatus, a sound absorbing material is commonly used. However, when a sound absorbing material is used, there is a disadvantage that a sound deadening effect is small with respect to a sound having a specific frequency. In addition, when the sound absorbing material is used, the apparatus becomes expensive accordingly.
Therefore, development of a paper sheet transporting apparatus and an image forming apparatus capable of reducing noise with an inexpensive apparatus configuration is desired.